// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

#pragma once

#include <set>
#include <string>
#include <unordered_map>

#include <alioth/filesystem.h>
#include <aries/parquet/platform.h>

namespace parquet::encryption {
    /// Stores encryption key material outside the Parquet file, for example in a separate
    /// small file in the same folder. This is important for “key rotation”, when MEKs have to
    /// be changed (if compromised; or periodically, just in case) - without modifying the
    /// Parquet files (often  immutable).
    class PARQUET_EXPORT FileKeyMaterialStore {
    public:
        /// Add key material for one encryption key.
        virtual void AddKeyMaterial(std::string key_id_in_file, std::string key_material) = 0;

        /// Get key material
        virtual std::string GetKeyMaterial(std::string key_id_in_file) = 0;

        /// After key material was added for all keys in the given Parquet file,
        /// save material in persistent store.
        virtual void SaveMaterial() = 0;

        /// Remove key material from persistent store. Used in key rotation.
        virtual void RemoveMaterial() = 0;

        /// Move key material to another store. Used in key rotation.
        virtual void MoveMaterialTo(std::shared_ptr<FileKeyMaterialStore> target_key_store) = 0;

        /// Returns the Set of all key IDs in this store (for the given Parquet file)
        virtual std::vector<std::string> GetKeyIDSet() = 0;

        virtual ~FileKeyMaterialStore() {
        }
    };
} // namespace parquet::encryption
